title: Biodegradable stereocomplex micelles based on dextran-block-polylactide as efficient drug deliveries.
abstract: Biodegradable stereocomplex micelles (SCMs) based on amphiphilic dextran-block-polylactide (Dex-b-PLA) were designed and used for efficient intracellular drug deliveries. The Dex-b-PLA copolymers were successfully synthesized by click reaction. The structures of the resultant copolymers were verified by (1)H NMR and FT-IR spectra. The formation of stable micelles through self-assembly driven by the stereocomplexation between enantiomeric l- and d-PLA blocks was characterized by transmission electron microscopy (TEM), dynamic laser scattering (DLS), and fluorescence techniques. It was interesting to observe that the SCMs showed lower critical micelle concentration values (CMCs) because of the stereocomplex interaction between PLLA and PDLA. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis provided information on the thermal and crystal properties of the copolymers and SCMs. The improved stability of SCMs should be attractive for intracellular drug delivery. Thus, a model anticancer drug doxorubicin (DOX) was loaded into micelles, and the in vitro drug release in was also studied. The release kinetics of DOX showed DOX-loaded SCMs exhibited slower DOX release. Confocal laser scanning microscopy (CLSM) and flow cytometry studies also showed that the DOX-loaded SCMs exhibited a slower drug release behavior. Meanwhile, the MTT assay demonstrated that DOX-loaded SCMs show lower cellular proliferation inhibition against HepG2. In sum, the micelles through self-assembly driven by stereocomplex interaction would have great potential to be used as stable delivery vehicles for pharmaceutical and biomedical applications.
authors.affiliation: Department of Chemistry, Northeast Normal University , Changchun 130024, P. R. China.
authors.forename: Ziwei
authors.initials: Z
authors.lastname: Zhao
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Yue
authors.initials: Y
authors.lastname: Cao
authors.forename: Chaoliang
authors.initials: C
authors.lastname: He
authors.forename: Xuesi
authors.initials: X
authors.lastname: Chen
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D057930:Click Chemistry; D003911:Dextrans / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D016503:Drug Delivery Systems; D056945:Hep G2 Cells; D006801:Humans; D008823:Micelles; D008958:Models, Molecular; D015394:Molecular Structure; D010316:Particle Size; D011091:Polyesters / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D013499:Surface Properties; D013501:Surface-Active Agents / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D003911:Dextrans; D008823:Micelles; D011091:Polyesters; D013501:Surface-Active Agents; C033616:poly(lactide)